“New Auditor Will Take Reigns in 2011” was the headline. Another article about money said that the “government refuses to seriously reign in spending.” Cash may indeed be king, but in both cases—and dozens of others found in recent months—the word the writers wanted was “rein.”

One has to do with horses (rein) and the other with royalty (reign). And while you could blame the misuse of the homophones on poor spelling, you could just as easily blame the slow creep of confusion. Garner’s Modern American Usage lists the misuse of “reign in” for “rein in” at Stage 2 of the Language-Change Index, meaning it has spread “to a significant fraction of the language community buy remains unacceptable in standard usage.” It’s only a step away from being “commonplace even among many well-educated people.”

If you can envision a king presiding over his kingdom, you want “reign.” If you can envision Roy Rogers trying to take control of Trigger, you want “rein.”

Happy Trails!

Merrill Perlman managed copy desks across the newsroom at The New York Times, where she worked for 25 years.